August 3, 1682 was a sunny, hot day. Gulls flew overhead and squawked as the Amity sailed up the Delaware River. From its deck, Thomas Holme scanned the horizon. While four of his children played, attended by three servants, this fifty-eight-year-old Quaker widower carefully observed the lay of the land. Along these woodland shores he would have to transform William Penn's grand vision into a reality. This would not be an easy job. On April 18, 1682, just before departing for Pennsylvania, Penn had appointed Holme his surveyor general and instructed him to go to Pennsylvania and lay out his "greene country towne."

Thomas Holme,"Portraiture of the City of Philadelphia in the Province of...

The story of Holme's great work really begins about a year before his arrival in Pennsylvania. After Penn received the charter for his colony from King Charles II, in July 1681, he had announced that he would establish a large town on the Delaware. Believing that his city could be built at Upland (present-day Chester, Pennsylvania), Penn sent three commissioners to buy the land for the project and to supervise settlement of the province.

But when his team arrived in the late fall 1681, they found that the Swedish settlers at Upland were unwilling to sell their property. The Swedes had been there for decades. Buying them out would be expensive, and forcing them to vacate would not only be un-Christian, but would alienate their affections. So the commissioners scouted out a new site upstream, then chose an area of undeveloped high ground known to the Lenape as Coaquannock – meaning "pine grove" – and known to the Swedes as the property of the three Swansson brothers.

Early in 1682, the commissioners bought this nearly mile long stretch of land. That summer the surveyor general began to lay out Philadelphia, the "City of Brotherly Love."

When Penn arrived in late October, he found the area that Holme plotted out too confined. Deciding to expand the town westward, he purchased a mile-long tract along the Schuylkill River from its Swedish owners, Peter Cock and Peter Rambo.

With this new property, the site for Penn's city stretched two miles east to west across a neck of land between the two rivers and one mile north to south along the Delaware. The giant rectangular lot comprised twelve thousand acres. In December 1682 Holme laid out Penn's "greene country towne" by imposing the proprietor's orderly grid plan on the site. The surveyor and the proprietor wanted the city to be a beautiful, healthful place that would be safe from fires like the one that destroyed London in 1666.

Holme oriented his grids around a large square in the center of the town and four smaller squares, one in each quadrant. These large, open spaces were to remain undeveloped as public parks; green spaces to keep the city healthy and prevent the spread of fire. Wide streets - fifty feet across - were also planned with an eye to fire prevention. The two main streets, Broad and High (today's Market Street), were 100-feet wide.

Holme initially named Philadelphia's streets after prominent English settlers. Objecting to this un-Quakerly memorialization of men, Penn renamed the streets that ran east and west after trees and plants that grew in his colony - Chestnut, Cranberry, Locust, Mulberry, Strawberry, "Wallnut," and Vine. He then numbered the streets that ran north to south.

Once the plan was complete, Holme made a map of the city both for reference and for promotional use. Finished in 1683 and entitled "A Portraiture of the City of Philadelphia," it presented the unique layout of Penn's emerging town.

Map of Welsh Tract, Facsimile of a part of Holme's Map, showing settlers of...

Before the proprietor left for England in 1684, he instructed his surveyor general to make another, more detailed map that would show the progress of settlement and land ownership. As he drew up the document, Holme placed the name of each landowner on the map within the outlines of their property. Holme finished this second map in 1687. Penn had the new map engraved and printed in London, hoping that it would motivate others to settle in his colony. This "Map of the Improved Part of the Province of Pennsilvania in America" shows the area from New Castle up to approximately ten miles above the falls of the Delaware and as far west as the headwaters of the Brandywine Creek.

Although Holme is best known as the surveyor of Penn's dream of a "greene country town" and for his two beautiful maps, he also was a member of the first Assembly of Pennsylvania and the Provincial Council. One of Penn's most trusted advisors, Holme assisted the young proprietor at an unsuccessful meeting with Lord Baltimore to try to resolve the disputed boundary between Maryland and Pennsylvania and participated in several important treaty conferences with the Lenape.

In addition to his duties as surveyor general – a post he held throughout his entire life – he also served as justice of the peace for Philadelphia County and as a commissioner of property. Holme died at Wellspring, his country estate in Bucks County's Dublin Township, in 1695.